This application relates to a turbine engine blade. More particularly, the application relates to an orientation of a cooling passage within the blade.
Turbine blades in turbine engines typically include cooling passages that are configured like a serpentine. Airfoil serpentine designs have forward and/or aft flowing serpentines. An inlet of the serpentine typically originates at a root of the turbine blade. The cooling passage extends from the inlet toward the tip before doubling back toward the root. The cooling passage may zigzag back and forth in this fashion in the fore-aft direction, that is, the leading-trailing edge direction.
The serpentine design described above is mainly driven by the core die process in which the die itself has to pull apart to create a ceramic core. The structure of the turbine blade is cast about the ceramic core. Typically, the final terminating up-pass passageway of the serpentine feeds film holes on both the pressure and suction sides of the airfoil. The pressure side film holes supply cooling fluid to fairly high sink pressures, and the suction side film holes supply cooling fluid to relatively low sink pressures. As a result, it is difficult to balance the flow of cooling fluid supplied from the same passageway to both the high and low pressure sides.
What is needed is a blade having a cooling passage that supplies cooling fluid in a more balanced manner to the pressure and suction sides of the blade.